1. Technical Field of the Invention
The invention relates to a fill valve assembly for a flush tank, having a housing that incorporates a vertical water-carrying channel that leads from an inlet that is to be fastened on the bottom of the flush tank to a float-controlled diaphragm valve that incorporates in the diaphragm a passage for the pressure equalization between a first chamber in front of the diaphragm and a second chamber behind the diaphragm, and having a pilot valve for actuating the diaphragm valve.
2. Prior Art
A fill valve assembly of the above type has become known in the prior art from U.S. Pat. No. 6,155,288. It is connected at an inlet connection piece to the bottom of the flush tank and incorporates a float-controlled diaphragm valve. After a flushing operation a float drops down and, via the pilot valve, opens the diaphragm valve. When the diaphragm valve is open, water flows vertically up to the valve seat of the diaphragm valve, which is located in a horizontal plane. After the valve seat, the water is guided down via a channel system into the flush tank and refills the same. A portion of the water after the valve seat is guided through a pipe to the trap of the toilet bowl to refill the trap. This refilling of the trap is required with so-called siphon traps. This is explained in more detail, for example, in U.S. Pat. No. 5,594,959.
A fill valve assembly of the above type has also become known from U.S. Pat. No. 5,623,961. The diaphragm valve is disposed at the upper end of a housing. When the diaphragm valve is open, the water flows vertically up to the diaphragm, which is disposed in a horizontal plane, and flows in a horizontal plane radially out, and in a channel system vertically down into the flush tank to refill the same. To refill the trap, a connection piece is disposed on the housing, and a portion of the water flows through the same into the trap.
The invention is based on the object to create a fill valve assembly of the above type that permits a quiet refilling of the flush tank while providing for a smaller overall height. It is a further object of the invention to create a fill valve assembly of the above type that permits a refilling of a siphon trap while providing for a smaller overall height. It is a further object of the invention to create a fill valve assembly of the above type whereby a backflow in case of a negative pressure in the supply line can effectively be prevented, and which is nonetheless""simple in its design.
In the inventive fill valve assembly the diaphragm valve is disposed laterally on the housing. The water that flows vertically up into the housing is deflected by 90xc2x0 and flows horizontally to the valve seat of the diaphragm valve. The lateral disposition of the diaphragm valve permits a significantly lower overall height of the fill valve assembly.
A particularly quiet filling is attained if, according to an improvement of the invention, the water, after passing the valve seat, flows into a rotation chamber, which extends in a horizontal plane. The water preferably flows into this rotation chamber tangentially.
According to an improvement of the invention means are disposed in the rotation chamber to prevent a backflow in case of a negative pressure. These are preferably designed such that when the diaphragm valve is open, the rotation chamber is open for the inflow of flushing water. During an inflow of air, however, this rotation is sealed off so that no water can enter from the flush tank into the pipe. According to a preferred embodiment the means are designed as a flap. In an improvement of the invention, this flap is fixed on the housing with a cover. This permits a particularly simple mounting and inspection.